Re: [PATCH] Introduce -nolibstdc++ option

[Alexandre Oliva <oliva@adacore.com>]

Hello, Gerald,

On Feb 11, 2023, Gerald Pfeifer <gerald@pfeifer.com> wrote:

> On Thu, 23 Jun 2022, Alexandre Oliva via Gcc-patches wrote:
>> Introduce -nostdlib++ option
>> 
>> Using g++ to link without libstdc++, as in g++.dg/abi/pure-virtual1.C,
>> is error prone, because there's no way to tell g++ to drop libstdc++
>> without also dropping libc and any other libraries that the target
>> implicitly links in.

> % grep -r nostdlib $WWWDOCS
> %

> Should this be documented in gcc-13/changes.html? Would you mind proposing 
> a snippet (or going ahead and pushing it)?

I can't make my mind up about this.

At first, the goal of adding the option was just to aid this specific
test.  But then, it transpired that other compilers offered a similar
option, with the spelling that we ended up using, so perhaps it would
make sense to document it, after all.

How about this, does this seem useful?

diff --git a/htdocs/gcc-13/changes.html b/htdocs/gcc-13/changes.html
index ff70d2eefecec..c1bbbfa28e18e 100644
--- a/htdocs/gcc-13/changes.html
+++ b/htdocs/gcc-13/changes.html
@@ -333,6 +333,9 @@ a work-in-progress.</p>
   <li>The <a href="https://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Dialect-Options.html#index-Wpessimizing-move"><code>-Wpessimizing-move</code></a>
     and <a href="https://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Dialect-Options.html#index-Wredundant-move"><code>-Wredundant-move</code></a>
     warnings have been extended to warn in more contexts.</li>
+  <li>The <a href="https://gcc.gnu.org/onlinedocs/gcc/Link_Options.html#index-nostdlib_002b_002b"><code>-nostdlib++</code></a>
+    option has been added, to enable linking with <code>g++</code>
+    without implicitly linking in the C++ standard library.</li>
 </ul>
 
 <h4 id="libstdcxx">Runtime Library (libstdc++)</h4>


-- 
Alexandre Oliva, happy hacker                https://FSFLA.org/blogs/lxo/
   Free Software Activist                       GNU Toolchain Engineer
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